1. Field of the Invention
The present invention relates to an ultrasonic wave oscillator and a production method therefor.
2. Description of the Related Art
FIG. 38 is a diagram showing a conventional ultrasonic wave oscillator (e.g., refer to a patent document 1 (i.e., Laid-Open Japanese Patent Application Publication No. 05-13542, pp 2-3, and FIGS. 1 and 2)).
An ultrasonic wave oscillator 160 shown in FIG. 38 is configured in such a manner that a silver electrode 163 is placed on either side of the top and bottom faces 162 of an electromechanical transducer element 161; a conductive member is over-coated on the outside of the silver electrode 163 on which a reinforcement part 164 is placed; the reinforcement part 164 and a lead unit 165 are connected together by a soldering 166; and the electromechanical transducer element 161 and lead unit 165 are electrically connected together.
As described above, the ultrasonic wave oscillator 160 shown in FIG. 38 is configured so that the electromechanical transducer element 161 and lead unit 165 are connected together by the soldering 166 and therefore a reliability relating to the electrical connection between the electromechanical transducer element 161 and lead unit 165 is high.
FIG. 39 is a diagram showing another conventional ultrasonic wave oscillator (e.g., refer to a patent document 2 (i.e., Laid-Open Japanese Patent Application Publication No. 11-231876, pp 2-3, and FIGS. 1 through 6)). Note that the same component sign is attached to the same configuration shown in FIG. 38.
An ultrasonic wave oscillator 167 shown in FIG. 39 is configured in such a manner that one side of the top and bottom faces 162 of the electromechanical transducer element 161 is pressed by a connection member 168 which is integrally formed with a lead unit 165; and the electromechanical transducer element 161 and lead unit 165 are electrically connected together.
As such, the ultrasonic wave oscillator 167 shown in FIG. 39 is configured in a manner that the electromechanical transducer element 161 is pressed by the connection member 168 to keep the electromechanical transducer element 161 always in contact with the connection member 168, and therefore a reliability relating to the electrical connection between the electromechanical transducer element 161 and lead unit 165 is high.
However, the ultrasonic wave oscillator 160 shown in FIG. 38 uses a soldering 166 for electrically connecting between the electromechanical transducer element 161 and lead unit 165, and therefore a heat of the soldering 166 is conducted to the electromechanical transducer element 161 when it is connected to the lead unit 165, bringing about the problem of causing a thermal damage to the electromechanical transducer element 161.
There is another problem of variations in a form and size of the ultrasonic wave oscillator 160 because a feature of the connection part between the electromechanical transducer element 161 and lead unit 165 cannot be correctly determined by a connection by the soldering 166.
Another problem is that a soldering work of the soldering 166 tends to produce a variation in a quality of a jointing depending on a degree of skill of a soldering temperature control technician, resulting in a propensity of a variation in a quality of the ultrasonic wave oscillator 160.
Another problem is that a certain large soldering area to some extent is required for suppressing a variation of a soldering area size, thereby increasing an overall size of the ultrasonic wave oscillator 160.
The associated problem is that if the ultrasonic wave oscillator 160 becomes large, it cannot be produced in a low cost.
Meanwhile, there is another connection method without using a soldering 166, that is, a use of a conductive adhesive. This method, however, is faced with a similar problem, as the connection method using the soldering 166, of causing a thermal damage on the electromechanical transducer element 161 because a quantity of the conductive adhesive is difficult to control and the conductive adhesive itself produces heat at the time of hardening.
Another problem facing the ultrasonic wave oscillator 167 shown in FIG. 39 is that it is configured to electrically connect the electromechanical transducer element 161 to the lead unit 165 by having a connection member 168 and a housing 169 sandwich the electromechanical transducer element 161, thus complicating in terms of its structure.
Another problem facing the ultrasonic wave oscillator 167 shown in FIG. 39 is that a variation of an overall size thereof is large due to the individual size variations of two components, i.e., the connection member 168 and housing 169, which exist independently and vary in size individually.
Meanwhile, in the case of absorbing a variation of an overall ultrasonic wave oscillator 167, shown in FIG. 39, by taking advantage of the fact of the connection member 168 deforming, the connection member 168 needs to be large to some extent, making it difficult to make the ultrasonic wave oscillator 167 compact eventually.
As in the case of the ultrasonic wave oscillator 160 shown in FIG. 38, another problem is that if the ultrasonic wave oscillator 167 is large, it cannot be produced in a low cost.
Accordingly, the purpose of the present invention is to provide an ultrasonic wave oscillator and a production method being low cost and allowing a miniaturization thereof, improving a reliability concerning an electrical connection and suppressing a thermal damage to an electromechanical transducer element when connecting a lead part thereto.
Patent document 1: Laid-Open Japanese Patent Application Publication No. 05-13542 (pp 2-3, and FIGS. 1 and 2)
Patent document 2: Laid-Open Japanese Patent Application Publication No. 11-231876 (pp 2-3, and FIGS. 1 through 6)